Esophagus

I'm in the same boat. I didn't receive their initial email and I'm worried I already heard back from them but the email was filtered out like the first time. Does it look bad to email them or is that acceptable?

When is the date for individuals to respond to their interview offer? At what point should rejections be sent out? Is it okay to email them to see if perhaps they sent an email but it didn't get through? Or is this frowned upon?